Cisco Cisco 1 GHz GainMaker Amplifier インストールガイド
Chapter 4 Troubleshooting
Low or Degraded Forward RF Signal
The forward RF signal can be measured at the amplifier module forward input and
forward output test points.
Low or Degraded Forward RF Signal Troubleshooting Table
Before you begin troubleshooting for a low or degraded forward RF signal, verify that
the amplifier is receiving the proper forward RF input signal from the upstream
amplifier.
Important: You cannot balance the amplifier without the proper forward RF input
Important: You cannot balance the amplifier without the proper forward RF input
signal.
Make sure you have configured the amplifier module according to the specifications in
Make sure you have configured the amplifier module according to the specifications in
the design print, and that the amplifier has warmed up for approximately one hour.
Make sure you are using the proper tilt reference when setting levels. An 870 MHz or 1
Make sure you are using the proper tilt reference when setting levels. An 870 MHz or 1
GHz design balanced at 550 MHz requires a corrected tilt reference to compensate for
the difference in carrier levels between 550 MHz and 870 MHz or 1 GHz. The tilt
reference at 550 MHz is lower than the tilt reference at 870 MHz or 1 GHz. Refer to the
tilt charts in Technical Information (on page 95) for more information.
Important: If the amplifier cover was ever removed, make sure it was properly
Important: If the amplifier cover was ever removed, make sure it was properly
reinstalled. Improperly reinstalling the amplifier module cover may result in RF signal
degradation.
Possible cause
Solution
Low or degraded forward RF signal
at the forward input test point.
Verify that the amplifier is receiving the proper
forward RF input signal from the upstream
amplifier.
Important: You cannot balance the amplifier
Important: You cannot balance the amplifier
without the proper forward RF input signal.
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